Merge branch 'gradients'

Readme.md

@@ -14,9 +14,9 @@
      [x] list of valid css colors
      [x] match canvas defaults (mostly, test suite from webkit would be nice)
      [x] transformations
+     [x] gradients
      [ ] make sure constructor names match
      [ ] anti aliasing
-     [ ] gradients
      [ ] Image
      [ ] patterns
      [ ] text

examples/gradients.js

@@ -0,0 +1,29 @@
+
+/**
+ * Module dependencies.
+ */
+
+var Canvas = require('../lib/canvas')
+  , canvas = new Canvas(320, 320)
+  , ctx = canvas.getContext('2d');
+
+// Create gradients
+var lingrad = ctx.createLinearGradient(0,0,0,150);
+lingrad.addColorStop(0, '#00ABEB');
+lingrad.addColorStop(0.5, '#fff');
+lingrad.addColorStop(0.5, '#26C000');
+lingrad.addColorStop(1, '#fff');
+
+var lingrad2 = ctx.createLinearGradient(0,50,0,95);
+lingrad2.addColorStop(0.5, '#000');
+lingrad2.addColorStop(1, 'rgba(0,0,0,0)');
+
+// assign gradients to fill and stroke styles
+ctx.fillStyle = lingrad;
+ctx.strokeStyle = lingrad2;
+
+// draw shapes
+ctx.fillRect(10,10,130,130);
+ctx.strokeRect(50,50,50,50);
+
+canvas.savePNG(__dirname + '/gradients.png');

lib/canvas.js

@@ -13,6 +13,7 @@ var canvas = require('../build/default/canvas')
   , colors = require('./colors')
   , Canvas = canvas.Canvas
   , Context2d = canvas.Context2d
+  , CanvasGradient = canvas.CanvasGradient
   , cairoVersion = canvas.cairoVersion;
 
 /**
@@ -118,6 +119,24 @@ Canvas.prototype.getContext = function(contextId){
   }
 };
 
+CanvasGradient.prototype.addColorStop = function(offset, color){
+  var rgba = exports.parseColor(color) || [0,0,0,1];
+  this.addColorStopRGBA(
+      offset
+    , rgba[0]
+    , rgba[1]
+    , rgba[2]
+    , rgba[3]);
+};
+
+Context2d.prototype.createLinearGradient = function(x0, y0, x1, y1){
+  return new CanvasGradient(x0, y0, x1, y1);
+};
+
+Context2d.prototype.createRadialGradient = function(x0, y0, r0, x1, y1, r1){
+  return new CanvasGradient(x0, y0, r0, x1, y1, r1);
+};
+
 /**
  * Set the fill style with the given css color string.
  *
@@ -126,13 +145,17 @@ Canvas.prototype.getContext = function(contextId){
  */
 
 Context2d.prototype.__defineSetter__('fillStyle', function(val){
-  var rgba = exports.parseColor(val) || [0,0,0,1];
-  this.lastFillStyle = rgba;
-  this.setFillRGBA(
-      rgba[0]
-    , rgba[1]
-    , rgba[2]
-    , rgba[3]);
+  if (val instanceof CanvasGradient) {
+    this.setFillPattern(val);
+  } else if ('string' == typeof val) {
+    var rgba = exports.parseColor(val) || [0,0,0,1];
+    this.lastFillStyle = rgba;
+    this.setFillRGBA(
+        rgba[0]
+      , rgba[1]
+      , rgba[2]
+      , rgba[3]);
+  }
 });
 
 /**
@@ -154,13 +177,17 @@ Context2d.prototype.__defineGetter__('fillStyle', function(){
  */
 
 Context2d.prototype.__defineSetter__('strokeStyle', function(val){
-  var rgba = exports.parseColor(val) || [0,0,0,1];
-  this.lastStrokeStyle = rgba;
-  this.setStrokeRGBA(
-      rgba[0]
-    , rgba[1]
-    , rgba[2]
-    , rgba[3]);
+  if (val instanceof CanvasGradient) {
+    this.setStrokePattern(val);
+  } else if ('string' == typeof val) {
+    var rgba = exports.parseColor(val) || [0,0,0,1];
+    this.lastStrokeStyle = rgba;
+    this.setStrokeRGBA(
+        rgba[0]
+      , rgba[1]
+      , rgba[2]
+      , rgba[3]);
+  }
 });
 
 /**

src/canvas.cc

@@ -37,7 +37,7 @@ Canvas::New(const Arguments &args) {
   if (!args[1]->IsNumber()) 
     return ThrowException(Exception::TypeError(String::New("height required")));
 
-  Canvas *canvas = new Canvas(args[0]->Uint32Value(), args[1]->Uint32Value());
+  Canvas *canvas = new Canvas(args[0]->Int32Value(), args[1]->Int32Value());
   canvas->Wrap(args.This());
   return args.This();
 }

src/canvas.h

@@ -13,6 +13,24 @@
 #include <node_object_wrap.h>
 #include <cairo.h>
 
+/*
+ * RGBA arg assertions.
+ */
+
+#define RGBA_ARGS(N) \
+  if (!args[N]->IsNumber()) \
+    return ThrowException(Exception::TypeError(String::New("r required"))); \
+  if (!args[N+1]->IsNumber()) \
+    return ThrowException(Exception::TypeError(String::New("g required"))); \
+  if (!args[N+2]->IsNumber()) \
+    return ThrowException(Exception::TypeError(String::New("b required"))); \
+  if (!args[N+3]->IsNumber()) \
+    return ThrowException(Exception::TypeError(String::New("alpha required"))); \
+  float r = args[N]->Int32Value(); \
+  float g = args[N+1]->Int32Value(); \
+  float b = args[N+2]->Int32Value(); \
+  float a = args[N+3]->NumberValue();
+
 using namespace v8;
 
 class Canvas: public node::ObjectWrap {
@@ -21,8 +39,6 @@ class Canvas: public node::ObjectWrap {
     static Handle<Value> New(const Arguments &args);
     static Handle<Value> SavePNG(const Arguments &args);
     inline cairo_surface_t *getSurface(){ return _surface; }
-
-  protected:
     Canvas(int width, int height);
 
   private:

src/context2d.cc

@@ -5,10 +5,11 @@
 // Copyright (c) 2010 LearnBoost <tj@learnboost.com>
 //
 
-#include "canvas.h"
-#include "context2d.h"
 #include <math.h>
 #include <string.h>
+#include "canvas.h"
+#include "context2d.h"
+#include "gradient.h"
 
 using namespace v8;
 using namespace node;
@@ -23,6 +24,12 @@ using namespace node;
   _.b = B / 255 * 1; \
   _.a = A; \
 
+#define SET_SOURCE(C) \
+  if (C##Pattern) \
+    cairo_set_source(ctx, C##Pattern); \
+  else \
+    SET_SOURCE_RGBA(C)
+
 /*
  * Set source RGBA.
  */
@@ -48,24 +55,6 @@ using namespace node;
   int width = args[2]->Int32Value(); \
   int height = args[3]->Int32Value();
 
-/*
- * RGBA arg assertions.
- */
-
-#define RGBA_ARGS \
-  if (!args[0]->IsNumber()) \
-    return ThrowException(Exception::TypeError(String::New("r required"))); \
-  if (!args[1]->IsNumber()) \
-    return ThrowException(Exception::TypeError(String::New("g required"))); \
-  if (!args[2]->IsNumber()) \
-    return ThrowException(Exception::TypeError(String::New("b required"))); \
-  if (!args[3]->IsNumber()) \
-    return ThrowException(Exception::TypeError(String::New("alpha required"))); \
-  float r = args[0]->Int32Value(); \
-  float g = args[1]->Int32Value(); \
-  float b = args[2]->Int32Value(); \
-  float a = args[3]->NumberValue();
-
 /*
  * Initialize Context2d.
  */
@@ -100,6 +89,8 @@ Context2d::Initialize(Handle<Object> target) {
   NODE_SET_PROTOTYPE_METHOD(t, "arc", Arc);
   NODE_SET_PROTOTYPE_METHOD(t, "setFillRGBA", SetFillRGBA);
   NODE_SET_PROTOTYPE_METHOD(t, "setStrokeRGBA", SetStrokeRGBA);
+  NODE_SET_PROTOTYPE_METHOD(t, "setFillPattern", SetFillPattern);
+  NODE_SET_PROTOTYPE_METHOD(t, "setStrokePattern", SetStrokePattern);
   proto->SetAccessor(String::NewSymbol("globalCompositeOperation"), GetGlobalCompositeOperation, SetGlobalCompositeOperation);
   proto->SetAccessor(String::NewSymbol("globalAlpha"), GetGlobalAlpha, SetGlobalAlpha);
   proto->SetAccessor(String::NewSymbol("miterLimit"), GetMiterLimit, SetMiterLimit);
@@ -130,6 +121,7 @@ Context2d::Context2d(Canvas *canvas): ObjectWrap() {
   _canvas = canvas;
   _context = cairo_create(canvas->getSurface());
   cairo_set_line_width(_context, 1);
+  fillPattern = strokePattern = NULL;
   globalAlpha = -1;
   RGBA(fill,0,0,0,1);
   RGBA(stroke,0,0,0,1);
@@ -337,6 +329,34 @@ Context2d::SetLineCap(Local<String> prop, Local<Value> val, const AccessorInfo &
   }
 }
 
+/*
+ * Set fill pattern, used internally for fillStyle=
+ */
+
+Handle<Value>
+Context2d::SetFillPattern(const Arguments &args) {
+  HandleScope scope;
+  // TODO: HasInstance / error handling
+  Context2d *context = ObjectWrap::Unwrap<Context2d>(args.This());
+  Gradient *grad = ObjectWrap::Unwrap<Gradient>(args[0]->ToObject());
+  context->fillPattern = grad->getPattern();
+  return Undefined();
+}
+
+/*
+ * Set stroke pattern, used internally for strokeStyle=
+ */
+
+Handle<Value>
+Context2d::SetStrokePattern(const Arguments &args) {
+  HandleScope scope;
+  // TODO: HasInstance / error handling
+  Context2d *context = ObjectWrap::Unwrap<Context2d>(args.This());
+  Gradient *grad = ObjectWrap::Unwrap<Gradient>(args[0]->ToObject());
+  context->strokePattern = grad->getPattern();
+  return Undefined();
+}
+
 /*
  * Set fill RGBA, used internally for fillStyle=
  */
@@ -344,7 +364,7 @@ Context2d::SetLineCap(Local<String> prop, Local<Value> val, const AccessorInfo &
 Handle<Value>
 Context2d::SetFillRGBA(const Arguments &args) {
   HandleScope scope;
-  RGBA_ARGS;
+  RGBA_ARGS(0);
   Context2d *context = ObjectWrap::Unwrap<Context2d>(args.This());
   RGBA(context->fill,r,g,b,a);
   return Undefined();
@@ -357,7 +377,7 @@ Context2d::SetFillRGBA(const Arguments &args) {
 Handle<Value>
 Context2d::SetStrokeRGBA(const Arguments &args) {
   HandleScope scope;
-  RGBA_ARGS;
+  RGBA_ARGS(0);
   Context2d *context = ObjectWrap::Unwrap<Context2d>(args.This());
   RGBA(context->stroke,r,g,b,a);
   return Undefined();
@@ -511,7 +531,7 @@ Context2d::Fill(const Arguments &args) {
   HandleScope scope;
   Context2d *context = ObjectWrap::Unwrap<Context2d>(args.This());
   cairo_t *ctx = context->getContext();
-  SET_SOURCE_RGBA(context->fill);
+  SET_SOURCE(context->fill);
   cairo_fill_preserve(ctx);
   return Undefined();
 }
@@ -525,7 +545,7 @@ Context2d::Stroke(const Arguments &args) {
   HandleScope scope;
   Context2d *context = ObjectWrap::Unwrap<Context2d>(args.This());
   cairo_t *ctx = context->getContext();
-  SET_SOURCE_RGBA(context->stroke);
+  SET_SOURCE(context->stroke);
   cairo_stroke_preserve(ctx);
   return Undefined();
 }
@@ -583,7 +603,7 @@ Context2d::FillRect(const Arguments &args) {
   Context2d *context = ObjectWrap::Unwrap<Context2d>(args.This());
   cairo_t *ctx = context->getContext();
   cairo_rectangle(ctx, x, y, width, height);
-  SET_SOURCE_RGBA(context->fill);
+  SET_SOURCE(context->fill);
   cairo_fill(ctx);
   return Undefined();
 }
@@ -599,7 +619,7 @@ Context2d::StrokeRect(const Arguments &args) {
   Context2d *context = ObjectWrap::Unwrap<Context2d>(args.This());
   cairo_t *ctx = context->getContext();
   cairo_rectangle(ctx, x, y, width, height);
-  SET_SOURCE_RGBA(context->stroke);
+  SET_SOURCE(context->stroke);
   cairo_stroke(ctx);
   return Undefined();
 }
@@ -616,7 +636,6 @@ Context2d::ClearRect(const Arguments &args) {
   cairo_t *ctx = context->getContext();
   cairo_set_operator(ctx, CAIRO_OPERATOR_CLEAR);
   cairo_rectangle(ctx, x, y, width, height);
-  SET_SOURCE_RGBA(context->fill);
   cairo_fill(ctx);
   cairo_set_operator(ctx, CAIRO_OPERATOR_OVER);
   return Undefined();

src/context2d.h

@@ -9,6 +9,7 @@
 #define __NODE_CONTEXT2D_H__
 
 #include "canvas.h"
+#include "gradient.h"
 
 typedef struct {
   float r, g, b, a;
@@ -18,6 +19,8 @@ class Context2d: public node::ObjectWrap {
   public:
     rgba_t fill;
     rgba_t stroke;
+    cairo_pattern_t *fillPattern;
+    cairo_pattern_t *strokePattern;
     float globalAlpha;
     static void Initialize(Handle<Object> target);
     static Handle<Value> New(const Arguments &args);
@@ -31,8 +34,11 @@ class Context2d: public node::ObjectWrap {
     static Handle<Value> ClosePath(const Arguments &args);
     static Handle<Value> Fill(const Arguments &args);
     static Handle<Value> Stroke(const Arguments &args);
+    static Handle<Value> SetSource(const Arguments &args);
     static Handle<Value> SetFillRGBA(const Arguments &args);
     static Handle<Value> SetStrokeRGBA(const Arguments &args);
+    static Handle<Value> SetFillPattern(const Arguments &args);
+    static Handle<Value> SetStrokePattern(const Arguments &args);
     static Handle<Value> BezierCurveTo(const Arguments &args);
     static Handle<Value> LineTo(const Arguments &args);
     static Handle<Value> MoveTo(const Arguments &args);

src/gradient.cc

@@ -0,0 +1,78 @@
+
+//
+// gradient.cc
+//
+// Copyright (c) 2010 LearnBoost <tj@learnboost.com>
+//
+
+#include "canvas.h"
+#include "gradient.h"
+
+void
+Gradient::Initialize(Handle<Object> target) {
+  HandleScope scope;
+  Local<FunctionTemplate> t = FunctionTemplate::New(Gradient::New);
+  t->InstanceTemplate()->SetInternalFieldCount(1);
+  t->SetClassName(String::NewSymbol("CanvasGradient"));
+
+  NODE_SET_PROTOTYPE_METHOD(t, "addColorStopRGBA", AddColorStopRGBA);
+  target->Set(String::NewSymbol("CanvasGradient"), t->GetFunction());
+}
+
+Handle<Value>
+Gradient::New(const Arguments &args) {
+  HandleScope scope;
+
+  // Linear
+  if (4 == args.Length()) {
+    Gradient *grad = new Gradient(
+        args[0]->NumberValue()
+      , args[1]->NumberValue()
+      , args[2]->NumberValue()
+      , args[3]->NumberValue());
+    grad->Wrap(args.This());
+    return args.This();
+  }
+
+  // Radial
+  if (6 == args.Length()) {
+    Gradient *grad = new Gradient(
+        args[0]->NumberValue()
+      , args[1]->NumberValue()
+      , args[2]->NumberValue()
+      , args[3]->NumberValue()
+      , args[4]->NumberValue()
+      , args[5]->NumberValue());
+    grad->Wrap(args.This());
+    return args.This();
+  }
+  
+  return ThrowException(Exception::TypeError(String::New("invalid arguments")));
+}
+
+Handle<Value>
+Gradient::AddColorStopRGBA(const Arguments &args) {
+  HandleScope scope;
+  if (!args[0]->IsNumber()) \
+    return ThrowException(Exception::TypeError(String::New("offset required"))); \
+  RGBA_ARGS(1);
+  Gradient *grad = ObjectWrap::Unwrap<Gradient>(args.This());
+  cairo_pattern_add_color_stop_rgba(
+      grad->getPattern()
+    , args[0]->NumberValue()
+    , r / 255 * 1
+    , g / 255 * 1
+    , b / 255 * 1
+    , a);
+  return Undefined();
+}
+
+Gradient::Gradient(double x0, double y0, double x1, double y1):
+  _x0(x0), _y0(y0), _x1(x1), _y1(y1) {
+  _pattern = cairo_pattern_create_linear(x0, y0, x1, y1);
+}
+
+Gradient::Gradient(double x0, double y0, double r0, double x1, double y1, double r1):
+  _x0(x0), _y0(y0), _x1(x1), _y1(y1), _r0(r0), _r1(r1) {
+  _pattern = cairo_pattern_create_radial(x0, y0, r0, x1, y1, r1);
+}

src/gradient.h

@@ -0,0 +1,29 @@
+
+//
+// gradient.h
+//
+// Copyright (c) 2010 LearnBoost <tj@learnboost.com>
+//
+
+#ifndef __NODE_GRADIENT_H__
+#define __NODE_GRADIENT_H__
+
+#include "canvas.h"
+
+using namespace v8;
+
+class Gradient: public node::ObjectWrap {
+  public:
+    static void Initialize(Handle<Object> target);
+    static Handle<Value> New(const Arguments &args);
+    static Handle<Value> AddColorStopRGBA(const Arguments &args);
+    Gradient(double x0, double y0, double x1, double y1);
+    Gradient(double x0, double y0, double r0, double x1, double y1, double r1);
+    inline cairo_pattern_t *getPattern(){ return _pattern; }
+
+  private:
+    double _x0, _y0, _x1, _y1, _r0, _r1;
+    cairo_pattern_t *_pattern;
+};
+
+#endif

src/node-canvas.cc

@@ -7,11 +7,13 @@
 
 #include "canvas.h"
 #include "context2d.h"
+#include "gradient.h"
 
 extern "C" void
 init (Handle<Object> target) {
   HandleScope scope;
   Canvas::Initialize(target);
   Context2d::Initialize(target);
+  Gradient::Initialize(target);
   target->Set(String::New("cairoVersion"), String::New(cairo_version_string()));
 }